(a) Field of the Invention
The present invention relates to a wood-type golf club head obtained by integraly joining a plurality of metallic shells.
(b) Description of Prior Art
For this kind of golf club head, there is proposed a wood-type golf club head disclosed in Japanese Patent Appln Laid-Open No. 6-335540, which discloses in FIGS. 1 and 2, a hollow wood-type golf club head obtained by integrally joining a main body made of titanium or titanium alloy having a shell-like sole and side-peripheral surface, a face member and a crown member. Such prior golf club head is advantageous when enlarging a sweet area because such a hollow structure of the main body enables the enlarging of the volume thereof. Further, there is also proposed another golf club head disclosed in Japanese U.M. Appln Laid-Open No. 60-177867, which discloses in FIG. 2, a golf club head having plural cavities in its back. The prior golf club head aimed at decreasing air resistance when swinging the same by forming plural cavities in the back of the head body which had been conventionally formed smooth. Additionally, there is further proposed another golf club head disclosed in Japanese Patent Appln Laid-Open No. 2-241469, which discloses in FIG. 1, a wood-type golf club head having small cavities formed along a peripheral portion of the head body by cutting process, thereby enchancing a sense of beauty.
Whereas, it is widely recognized that for enlargement of so-called a sweet area, a wood-type golf club head (hereinafter called head) should have an elongated distance between the CG of the head body and the face. However, according to the prior golf club heads, the face must be formed to a preset thickness because of the requirement for the strength thereof at the time of striking balls, therefore, a predetermined weight would be inevitably required for thickening the face. As a result, there has been a problem such that a golf club head cannot be formed as you like.